the uk energy storage supergen consortium prof peter hall dept chemical engineering university of...

The UK Energy Storage Supergen Consortium

Prof Peter Hall

Dept Chemical Engineering

University of Strathclyde

Glasgow

Scotland

Need for Energy StorageEven though UK energy grid is based upon

centralised power sources there is considerable energy storage built into systemCoal stocks peaked at 24,000 kTonnes at end of 2009

(~55,000 GWh electrical)Pumped hydro only accounts for equivalent of 3,500

Tonnes coalElectrification of transport will double electrical

demand and have immediate effect on CO2 emissions

Supergen partnershipSix Universities:

Fundamental materials understanding: Cambridge, Bath

Materials, device production: St Andrews, Strathclyde, Newcastle

Materials scale-up: Oxford, StrathclydeTransport engineering: StrathclydeGrid engineering: Bath

Technology problem areasHigh cost/low energy density of Li based

batteriesMost supercapacitors manufacturers

base technology around organic liquid electrolytesLow voltage devices (~6-7 V)High production costsTechnology awareness and applications

Anode

LiCathode

O2Organic Electrolyte

Li+

O2

Li2O2

Carbon Electrode

2Li+ + 2e- + O2 Li2O2

Li battery research Li/O2 cells

Vtotal = 1.434 cm3/gSBET = 1725 m2/gPS = 5.60 nm

Vtotal = 1.320 cm3/gSBET = 1545 m2/gPS = 6.10 nm

Vtotal = 1.150 cm3/gSBET = 1290 m2/gPS = 6.15 nm

Capacity of Li ion batteries

Increased capacity

Li/O2 battery performance

Charge / Discharge cycling of ACRF003-950 carbon

Supercapacitor researchDevelopments to increase

performance/cost ratio includeAqueous electrolyte devices based on high

grade carbonsIonic liquid based supercapacitors Development of pseudocapacitors

Future developments are materials based

I n d i a U r b a n D r i v e C y c l e , b a t t e r i e s o n l y

- 1 0 0

- 5 0

0

5 0

1 0 0

1 5 0

2 0 0

2 5 0

3 0 0

0 1 0 0 2 0 0 3 0 0 4 0 0 5 0 0 6 0 0 7 0 0 8 0 0 9 0 0

T i m e ( s )

Battery Current (A)

I n d i a U r b a n D r i v e C y c l e , o p t i m i s e d f o r b a t t e r y l i f e t i m e

- 1 0 0

- 5 0

0

5 0

1 0 0

1 5 0

2 0 0

2 5 0

3 0 0

0 1 0 0 2 0 0 3 0 0 4 0 0 5 0 0 6 0 0 7 0 0 8 0 0 9 0 0

T i m e ( s )

Battery Current (A)

Battery lifetime extension

Materials structure/performance

0

0.5

1

1.5

2

2.5

3

0 200 400 600 800 1000

Time (s)

Vo

lta

ge

(V

)

ACRF200ACRF300ACRF500ACRF750

Sample 2

mA

4

mA

8

mA

16

mA

32

mA

64

mA

Emax

Wh/g

EMImBF4 Capacitance F/g

ACRF200 170.1 148.9 137.4 128.9 120.9 113.95 2231.9

ACRF300 147.6 141.0 136.2 126.95 123.25 116.5 1845

ACRF500 113.1 106.3 101.8 97.7 92.7 88.8 1413.8

ACRF750 77.6 71.4 66.2 60.3 53.7 46.6 1024.7

Conclusions/PlansSubstantial materials developments have taken

placeRechargeable Li/O2 cells have been

demonstrated at the button cell levelOur aim is to produce viable pouch cells

within three yearsFundamental improvements have been made to

the understanding of mass transfer in ionic liquid based supercapacitorsWe aim to produce commercial aqueous

bipolar supercapacitors within two years

www.energystorage.org.uk